Volvo Buses


How Volvo Buses works with HMI and safety

Human Machine Interface (HMI) plays a crucial role in Volvo Buses’ safety systems. Acting System Owner for Driver Environment Ulrika Larborn explains how it creates a seamless, intuitive interaction with the driver for safer bus operations.
Volvo Buses’ HMI expert Ulrika Larborn sitting in the driver environment
Ulrika Larborn says good HMI ensures that drivers have an intuitive experience and feel safe and supported in all types of traffic situations.

What is HMI?
“HMI stands for Human Machine Interface - the interface between a human and a machine. This two-way interaction can take place in many different ways - for example through sound, light or vibrations. An example of how HMI works can be when you press a button to start your phone. Why do you choose to press that particular button? It is the result of both your previous experience and the knowledge you have acquired, but it is also about the design of the button itself - its colour, shape and placement. When you press this button, the machine, or in this case the phone, lets you know that it has registered your action - perhaps with a vibration followed by the light of the display. This is HMI - it is part of our everyday lives and it is all around us.”

How does Volvo work with HMI?
“We benefit from having a dedicated, in-house HMI research and development team within the Volvo Group. At Volvo Buses, HMI encompasses everything from the choice and design of components and their placement to all the information shown on the instrument displays. Drivers should also recognize that they are operating a Volvo vehicle, so we collaborate within Volvo Group to ensure that we follow the same HMI strategy, although of course adjustments are needed as our products, drivers and their environments differ. When it comes to the information we show to a bus driver, we need to think about its purpose and in what situation they should receive it. What is the most effective and safest way to communicate with the driver in that specific situation? Should we have a visual warning or information, or use sound or vibration? Or should we use a combination?
“Right now, we are putting a lot of effort into designing the HMI for our instrument displays. We have to decide what information is most important to the driver and work out how to design the HMI to evoke wanted behaviour. We have many discussions like this to ensure that these components fit seamlessly into our product.”

Why is HMI so important for bus safety?

“Bus drivers have a very big responsibility - they transport passengers and they drive in environments where many people are present. It is incredibly important that the driver interacts with a good HMI so that he or she can safely drive the bus in all of these environments. It is also crucial that the HMI is intuitive and that the driver gets the right active safety system information at the right time and in the right place.
Today, we can get so much information from the vehicle. For the driver to be able to absorb this information in a clear and simple way, the HMI must be well thought out. The driver must be able to find the right button or information without having to search for it, so that they can keep their eyes on the road. A very important part of the work is also not to overload the drivers with information but to find a good balance.”

How is Volvo Buses’ HMI developed to intuitively communicate with and support the driver?
“We use HMI to ensure that drivers have a very simple, intuitive, user-friendly and consistent experience that makes them feel safe and supported in all types of traffic situations. We also try to make sure that our HMI solutions meet the different needs of our users. So regardless of experience or knowledge, drivers should be able to operate our buses in a very safe and secure way. To create this understanding, we conduct observations and user studies. We also interview drivers to gain knowledge about how they work to understand what type of HMI works best for them. When we develop something new, we do a lot of testing in simulators and rigs, but we are also out driving in real buses, both with our team of experts and our test drivers. By developing an effective HMI, the driver will get the support he or she needs in a given situation. For example, it should be clear what a safety warning is about and what we want the driver to do in that situation. At Volvo, this is a continuous development - we are constantly adding more and more systems to our vehicles that the driver may need or can at least interact with. It is also important to carefully weigh up when the driver needs information and when they don’t. Some information is not necessary while driving for example. Instead, we make it possible to interact with these functions when the bus is stationary.”

What is the next step for HMI development at Volvo?
"At the moment we are in the next generation of HMI and are working to see how we can simplify the flow of information to the driver even more. Today, the number of displays is increasing in the driver environment. This is especially true for city buses, where there are many separate operator systems that constantly demand the driver's attention. At Volvo Buses, we want to remove this unnecessary stress for the driver. Some functions can be placed in the display while others may need to be kept as buttons or stalks as this can be easier for the driver to find them. It’s a balancing act that is very important, especially when it comes to safety. For us, safety is absolutely the most important thing we work with. Our primary goal is for the driver to be able to focus on the road and be able to see potential dangers and risks. We believe every driver, regardless of experience, should feel supported, safe and secure when they drive a Volvo bus.”

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